The Traffic-Relative Observability and Lateral Allocation Principle (TROLAP): A Conditional Theory of Pedestrian Position Allocation, Traffic Awareness, and Risk-Constrained Walking

This paper proposes the Traffic-Relative Observability and Lateral Allocation Principle (TROLAP), a conditional theoretical framework for examining how pedestrian position allocation on a constrained roadside walking facility may interact with traffic-relative hazard observability, vehicular exposure, maneuverability, and pedestrian interaction. The primary case, termed the Asymmetric Traffic-Observability Pairing Case (ATOP), concerns two pedestrians walking in opposite longitudinal directions along a path adjacent to a dominant vehicle flow. Pedestrian A moves against the traffic direction and may have direct visual access to approaching vehicles. Pedestrian B moves with the traffic direction and may have reduced rearward awareness unless additional scanning occurs. The proposed Counterflow-Outer / Sameflow-Inner Configuration (COSIC) places A on the road-facing portion of the designated pedestrian path and B on the inner portion. The proposal is not assumed to be universally safer. Its performance depends on the interaction between timely detection, physical exposure, available clearance, response capacity, path geometry, and the constraints imposed by the surrounding environment. The paper defines the Risk-Constrained Traffic-Relative Lateral Allocation Mechanism (RCTLAM), a formal variable system, spatial feasibility constraints, candidate risk objectives, a research hypothesis set, fourteen theoretical layers, twelve research domains, thirty validation scenarios, and a staged research protocol. The mathematical expressions specify a proposed modelling architecture rather than an empirically calibrated crash-prediction model. No original empirical dataset or completed validation study is claimed. The principal research question is whether the proposed allocation produces a lower estimated total risk than relevant feasible alternatives under prespecified conditions. The framework is designed to support reproducible comparison, falsification, and restricted generalization rather than an unconditional safety rule.pedestrian safety; traffic-relative observability; lateral position allocation; pedestrian dynamics; risk-constrained optimization; human factors; COSIC; RCTLAM